[PATCH v10 18/33] counter: Return error code on invalid modes
William Breathitt Gray
vilhelm.gray at gmail.com
Fri Mar 19 11:00:37 GMT 2021
Only a select set of modes (function, action, etc.) are valid for a
given device configuration. This patch ensures that invalid modes result
in a return -EINVAL. Such a situation should never occur in reality, but
it's good to define a default switch cases for the sake of making the
intent of the code clear.
Cc: Syed Nayyar Waris <syednwaris at gmail.com>
Cc: Kamel Bouhara <kamel.bouhara at bootlin.com>
Cc: Fabrice Gasnier <fabrice.gasnier at st.com>
Cc: Maxime Coquelin <mcoquelin.stm32 at gmail.com>
Cc: Alexandre Torgue <alexandre.torgue at st.com>
Cc: David Lechner <david at lechnology.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray at gmail.com>
---
drivers/counter/104-quad-8.c | 20 +++++++----
drivers/counter/microchip-tcb-capture.c | 6 ++++
drivers/counter/stm32-lptimer-cnt.c | 10 +++---
drivers/counter/ti-eqep.c | 45 +++++++++++--------------
4 files changed, 46 insertions(+), 35 deletions(-)
diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 09d779544969..b7d6c1c43655 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -273,6 +273,10 @@ static int quad8_function_set(struct counter_device *counter,
*scale = 2;
mode_cfg |= QUAD8_CMR_QUADRATURE_X4;
break;
+ default:
+ /* should never reach this path */
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
}
}
@@ -349,7 +353,7 @@ static int quad8_action_get(struct counter_device *counter,
case QUAD8_COUNT_FUNCTION_PULSE_DIRECTION:
if (synapse->signal->id == signal_a_id)
*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
- break;
+ return 0;
case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
if (synapse->signal->id == signal_a_id) {
quad8_direction_get(counter, count, &direction);
@@ -359,17 +363,18 @@ static int quad8_action_get(struct counter_device *counter,
else
*action = QUAD8_SYNAPSE_ACTION_FALLING_EDGE;
}
- break;
+ return 0;
case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
if (synapse->signal->id == signal_a_id)
*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
- break;
+ return 0;
case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
- break;
+ return 0;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
-
- return 0;
}
static const struct counter_ops quad8_ops = {
@@ -529,6 +534,9 @@ static int quad8_count_mode_set(struct counter_device *counter,
case COUNTER_COUNT_MODE_MODULO_N:
cnt_mode = 3;
break;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
mutex_lock(&priv->lock);
diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c
index 51b8af80f98b..0c9a61962911 100644
--- a/drivers/counter/microchip-tcb-capture.c
+++ b/drivers/counter/microchip-tcb-capture.c
@@ -133,6 +133,9 @@ static int mchp_tc_count_function_set(struct counter_device *counter,
bmr |= ATMEL_TC_QDEN | ATMEL_TC_POSEN;
cmr |= ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_ABETRG | ATMEL_TC_XC0;
break;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
regmap_write(priv->regmap, ATMEL_TC_BMR, bmr);
@@ -226,6 +229,9 @@ static int mchp_tc_count_action_set(struct counter_device *counter,
case MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE:
edge = ATMEL_TC_ETRGEDG_BOTH;
break;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
return regmap_write_bits(priv->regmap,
diff --git a/drivers/counter/stm32-lptimer-cnt.c b/drivers/counter/stm32-lptimer-cnt.c
index c19d998df5ba..78f383b77bd2 100644
--- a/drivers/counter/stm32-lptimer-cnt.c
+++ b/drivers/counter/stm32-lptimer-cnt.c
@@ -206,9 +206,10 @@ static int stm32_lptim_cnt_function_set(struct counter_device *counter,
priv->quadrature_mode = 1;
priv->polarity = STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES;
return 0;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
-
- return -EINVAL;
}
static ssize_t stm32_lptim_cnt_enable_read(struct counter_device *counter,
@@ -326,9 +327,10 @@ static int stm32_lptim_cnt_action_get(struct counter_device *counter,
case STM32_LPTIM_ENCODER_BOTH_EDGE:
*action = priv->polarity;
return 0;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
-
- return -EINVAL;
}
static int stm32_lptim_cnt_action_set(struct counter_device *counter,
diff --git a/drivers/counter/ti-eqep.c b/drivers/counter/ti-eqep.c
index 65df9ef5b5bc..878725c2f010 100644
--- a/drivers/counter/ti-eqep.c
+++ b/drivers/counter/ti-eqep.c
@@ -157,44 +157,39 @@ static int ti_eqep_action_get(struct counter_device *counter,
* QEPA and QEPB trigger QCLK.
*/
*action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES;
- break;
+ return 0;
case TI_EQEP_COUNT_FUNC_DIR_COUNT:
/* In direction-count mode only rising edge of QEPA is counted
* and QEPB gives direction.
*/
- switch (synapse->signal->id) {
- case TI_EQEP_SIGNAL_QEPA:
- *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE;
- break;
- default:
+ if (synapse->signal->id == TI_EQEP_SIGNAL_QEPB)
*action = TI_EQEP_SYNAPSE_ACTION_NONE;
- break;
- }
- break;
+ else
+ *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE;
+ return 0;
case TI_EQEP_COUNT_FUNC_UP_COUNT:
case TI_EQEP_COUNT_FUNC_DOWN_COUNT:
/* In up/down-count modes only QEPA is counted and QEPB is not
* used.
*/
- switch (synapse->signal->id) {
- case TI_EQEP_SIGNAL_QEPA:
- err = regmap_read(priv->regmap16, QDECCTL, &qdecctl);
- if (err)
- return err;
-
- if (qdecctl & QDECCTL_XCR)
- *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES;
- else
- *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE;
- break;
- default:
+ if (synapse->signal->id == TI_EQEP_SIGNAL_QEPB) {
*action = TI_EQEP_SYNAPSE_ACTION_NONE;
- break;
+ return 0;
}
- break;
- }
- return 0;
+ err = regmap_read(priv->regmap16, QDECCTL, &qdecctl);
+ if (err)
+ return err;
+
+ if (qdecctl & QDECCTL_XCR)
+ *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES;
+ else
+ *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE;
+ return 0;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
+ }
}
static const struct counter_ops ti_eqep_counter_ops = {
--
2.30.2
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